I have been using Google geocode API to either get an address from coordinates or the other way around. This API have always been more restricted than others like Maps. A few days ago I learned that the price have increased by 10x.
Until that change, our usage was bellow the $200 of free monthly credit, but with the increase, we will be way above. As long as the APIs was free, we didn't take too much time to think when implementing features requiring geocode data.
It's important to be mindful when using free services. As your user base grow or if the price change, you might have to rework parts of your app.